The subject matter relates generally to wireless communication devices and to antenna assemblies or apparatuses that may be used by wireless communication devices and that are configured to reduce or re-direct radiation to lower the specific absorption rate (SAR).
Wireless communication devices are increasingly used by consumers and have an expanding number of applications within a variety of industries. Examples of such wireless devices include mobile phones, tablet computers, notebook computers, laptop computers, and handsets. These devices often include one or more integrated antennas that allow for wireless communication within a communication network. Recently, there have been two conflicting market demands for wireless devices. Users generally demand wireless devices that are smaller or weigh less, but the users also desire better performances and/or a greater number of capabilities. For example, wireless devices now operate within multiple frequency bands and are capable of selecting such bands for different networks. Features that have improved recently include data storage, battery life, and camera performance, among other things.
To provide smaller devices with improved performances and more capabilities, manufacturers have attempted to optimize the available space within the wireless device by resizing components of the wireless device or by moving the components to different locations. For example, the size and shape of the antenna may be reconfigured and/or the antenna may be moved to a different location. The number of available locations for an antenna, however, is limited not only by other components of the wireless device, but also by government regulations and/or industry requirements, such as those relating to SAR.
With respect to portable computers, such as laptops, notebooks, tablets, and convertible computers that can operate in laptop or tablet modes, antennas are positioned either within a section of the computer that includes a display or a base section that includes the keyboard. Regardless of the location, however, it is likely that an individual's body will be positioned adjacent to the antenna at some point. For example, individuals often place a portable computer on their laps or fold and grip convertible computers when in the tablet mode. Even at these moments, government and/or industry requirements require that the SAR does not exceed a predetermined level. Accordingly, antenna designs that reduce the amount of radio frequency (RF) exposure to the individual's body without significantly limiting performance are desired.